Variable capacity pump



Aug. 8, 1950 R. H. FREDERICK VARIABLE CAPACITY PUMP 5 Sheets-Sheet 1 Filed June 5, 1947 m k m .w W P. d m F H l e U M R t hm mm km Aug. 5, 1950 R. H. FREDERICK VARIABLE CAPACITY PUIIP s sheets-sheet 2 Filed June 5, 1947 Rheuel H. Frederick Aug. 8, 1950 R. H. FREDERICK VARIABLE CAPACITY PUIIP -5 Sheets-Sheet 3 Filed June 5, 1947 I Inventor Rheue/ H. Frederick 4062 By W I a Attorneys Aug. 8,' 1950 R. H. FREDERICK VARIABLE CAPACITY Full? 5 Sheets-Sheet 4 Filed June 5, 194'? Inventor Rheue/ H. Frederick Aug. 8, 1950 R. H. FREDERICK VARIABLE CAPACITY PUIIP Filed June 5, 194? 5 Shqets-Sheet 5 Fig. 5.

Fig. I6.

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Inventor Rh eue/ H. Frederick WW 3M Patented Aug. 8, 1950 2,517,862 VARIABLE CAPACITY PUMP Rheuel H. Frederick, High Bridge, N. J.

Application June 5, 1947, Serial No. 752,617

6 Claims.

This invention relates to a variable capacity pump and has for its primary object to facilitate the varying of the capacity of the pump without interfering with its operation.

Another object is to enable the capacity of the pump to be varied from zero to full capacity by the simple rotation of a control shaft.

The above and other objects may be attained by employing this invention which embodies among its features a hollow circular casing having a pair of diametrically opposed ports opening thereinto, a rotor mounted in the casing for' concentric rotation about the longitudinal axis thereof, vanes mounted in the rotor to move in radial planes longitudinally of the rotor and a cam mounted in the casing to move the vanes longitudinally of the rotor as the rotor rotates about the axis of the casing.

Other features include means to alter the position of the cam while the pump is in operation.

In the drawings:

Figure 1 is a longitudinal sectional view through a pump embodying the features of this invention taken through the diametrically opposed P r Figure 2 is a view similar to Figure 1 taken on a plane perpendicular to the plane of Figure 1,

Figure 3 is a view similar to Figure 1 illustrating portions of the rotor broken away to show the cam and vanes,

Figure 4 is a side view of the pump, certain portions of the casing being broken away to more clearly illustrate certain detafls of construction.

Figure 5 is a transverse sectional view taken substantially along the line 5-5 of Figure 1,

Figure 6 is a transverse sectional view, taken substantially along the line 6--6 of Figure 1,

Figure 7 is a transverse sectional view taken substantially along the line of Figure 2,

Figure 8 is a perspective view of the fin carrying end plate for the pump casing,

Figure 9 is a perspective view of the pump shaft and rotor, s

Figure 10 is a side view of the shaft'showing the rotor removed and certain portions being illustrated in section more clearly to show certain details of construction,

Figure 11 is a perspective view of the circular block forming the core of the rotor,

Figure 12 is a perspective view of the sleeve forming the outer shell of the rotor, certain portions being broken away more clearly to illustrate certain details of construction,

Figure 13 is a perspective view of one of the rotor vanes,

Figure 14 is a perspective view of the cam member controlling cup, beFigurelti is a perspective view of the cam mem- Figure 16 is a longitudinal sectional view through the cam member illustrated in Figure 15,

Figure 17 is a perspective view of the end plate for the cylindrical body at the end opposite the rotor, and

Figure 18 is an end view of the control shaft, pinion and rack.

Referring to the drawings in detail, this improved pump designated generally 20 comprises a cylindrical body 2| formed with a longitudinal circular bore 22 and having intermediate its ends diametrically opposed ports 23 and 24 each of which is surrounded by a coupling flange having formed therein an annular row of internally screwthreaded sockets 25 by means of which pipes may be coupled to the pump. Formed internally of the cylindrical body 2| and extending there- 7 around in alignment with the ports are arcuate ence to the drawings. As illustrated in the drawings, the ports 23 and 24, as well as the recesses 26 and 21 are formed in the body near one end.

Opposite ends of the body are provided with annular rows of radially spaced internally screwthreaded sockets 29 and 30 and the bore 22 is enlarged as at 3| at the end opposite that near which the ports are formed to provide an annular internal shoulder 32 the purpose of which will be more fully hereinafter explained.

Closing the end of the body 2| adjacent the ports 23 and 24 is a cap 33 which as illustrated is coupled to the body by means of machine screws 34 which enter the sockets 29 securely to hold the cap in place. This cap is equipped near its inner end with a suitable anti-friction bearing 35 and at its outer end with an axially extending socket 36 for the reception of packing rings 36' and a tubular packing nut 31. Extending longitudinally through the cap between the anti-friction bearing 35 and the socket 36 is a longitudinal bore 38 which aligns axially with the longitudinal axis of the bore 22 in the body 2|.

Clamped' against the end of the body 2| by the, cap 22 is a, plate 39 which is formed with an axial opening 49 which aligns with the longitudinal axis of the body 2|, and formed on the face of the plate 39 which is disposed against the body 2| are diametrically opposed fins 4| which project toward but terminate short of the ports 28 and 24.

Mounted for rotation 'in the anti-friction bearings 85 and extending axially through the bore 38 and into the bore 22 of the housing 2| is a shaft 42. This shaft extends through the packing rings 88' and the packing nut 81 to the ex- Formed intermediate the ends of the shaft in uniformly spaced relation about the periphery are longitudinal grooves 48, and fixed to the shaft adiacent the inner ends of the fins 4| is a circular block 49 having formed therein a plurality of radial grooves 58 which open through its periphery, and one end of the block. These groove 50 align with the grooves 48 in the shaft, and serve as guides for the sliding vanes to be more fully hereinafter described. Fitted over the cylindrical block 49 is a sleeve which is provided on its inner surface with radially spaced longitudinal groove 52 which open outwardly through one end, and align with the grooves 48 and 50 of the shaft 42 and sleeve 49 respectively. As illustrated in Figure 12, the bottom walls of the grooves 52 incline outwardly toward the centrally located aperture 55. The outer ends of the vanes 54 are also provided with oppositely inclined faces 58 which meet midway between opposite side edges of their respective vanes to form peaks 51. The slope of the faces 58 coincides with the slope of the bottom walls of the grooves 52.

Fixed to the end of the cylindrical body 2| opposite the cap 33 is a cover plate 58 which is provided with an inwardly extending annular flange 59 and an outwardly extending tubular boss 69. The cover plate is provided with an axial opening 6| the axis of which aligns with the longitudinal axis of the body 2| and seated in the outer end of the tubular boss 68 are suitable packing rings 82 which are held in place by a tubular packing nut 63.

Clamped between the inner ends of the annular flange 59 and the shoulder 32 is a plate 84 carrying an inwardly extending socket 65 in which an anti-friction bearing 68 is fitted. Mounted for rotation in the bearing 86 and extending through an axial opening 81 in the plate 84 is a stub shaft 88 carrying at its outer end a transversely extending rib 69 the purpose of which will be more fully hereinafter explained. A coupling flange 18 is carried on the inner end of the shaft, and coupled which the anti-friction bearing 41 previously referred to is fitted. Coupled to the inner end of the cup 1| as by cap screws 12 is a cam designated generally 18. Formed on the plate 84 and extending inwardly therefrom at diametrically op-r posite points are fins 14 which extend the full length of the bore 22 between the plate 64 and the cam 18 to divide the space within the housing into two separate chambers.

The cam 18 above referred to comprises a cylindrical body having formed therein an axial bore 18 the axis of which aligns with the longitudinal axis of the body 2|, and communicating with the bore 18 at one end of the cam body 15 is an enlarged socket 11 in which the anti-friction bearing 48 previously referred to is fitted. Formed on the end of the cam body 15 opposite the socket I1 is a tubular extension 18 provided at its end with a cam face 19 which as illustrated in Figures 2, 3 and 4 is adapted to engage the ends of the vanes 54 opposite those entering the slots 58 in the cylindrical block 49. As shown in Figures 2, 8 and 4 the tubular extension 18 fits into the open end of the sleeve 5|.

Mounted for rotation in the bore 8| and the packing nut 83 is a control shaft 88, the inner end of which is provided with a transversely extending groove 8| for the reception of the transverseLv extending rib 89 onthe stub shaft 58. The outer end of the control shaft 80 has secured thereto a pinion 82 which has meshing engagement with a rack bar 83 to one end of which is coupled a suitable link 84 which in turn is coupled to a hand actuated lever 85 so that upon moving the lever, the shaft 88 will be rotated to move the cam I8 about the longitudinal axis of the pump.

In assembling the device the shaft 42 is mounted in an anti-friction bearing to extend longitudinally through the cap 33' with the rotor comprised of the cylindrical block 49 and sleeve 5| mounted on the shaft adjacent the fins 4| of the disk 99. The shaft, rotor and disk are then assembled with the cylindrical body 2| and the screws 84 threaded into the sockets 29 with the fins 4| aligning longitudinally with the lands 28 previously described. The rotor will thus be positioned to bring the passages 53 into alignment with the recesses 25' and 21 and the ports 23 and 24. The cam member 18 is then entered through the opposite end of the bore 22 in the body 2| so that the cam face will bear against the rotor blades or vanes 54 and the portion 44 of the shafts 42 will be mounted in the bearing 46 so that the cam member 13 may be rotated independently of the shaft 42. The cup-shaped member II is then fastened to the cam member 18 by the screws 12 so that the portion of the shaft 42 will enter the bearing 41 housed within the cup 1|. The stub shaft 88 is fastened to the cup-shaped member 1| to extend in a direction opposite the cam member 18 in axial alignment with the shaft 42. The anti-friction bearing 86 is then fitted over the stub shaft 88 and the plate 54 is fitted over the bearing and rests against the shoulder 82 with the fins 14 aligning with the fins 4| and lands 28. after which the end member 58 i attached to the body 2| with the slot 8| of the control shaft 89 receiving the tongue or rib 89 on the end of the stub shaft 68. It will be seen that the fins 4t and 14 when in alignment with the lands 28 will divide the body 2| longitudinally into a high pressure chamber and a low pressure chamber which are not the pumping or working to the flange 10 is a cup-shaped member II in '78 chambers of the pump. with the pinion 82 fixed to the control shaft 80 it will be obvious that upon moving the lever 85 as through the medium of a suitable hand control, the rack 83 will be moved to rotate the pinion 82 and thus impart rotary motion to the control shaft 80, the stub shaft 68, the cup-shaped member II and the cam member 13 so as to alter the position of the high point of the cam face 19 about the axis of the pump. In this way, the movements of the vanes 54 may be regulated from zero to full capacity.

In use, the port 23 is coupled to a suitable source of fluid supply and the discharge port 24 may be coupled to a discharge pipe. Upon setting the shaft 42 into motion through the medium of the drive flange 43 it will be obvious that the rotor on the shaft will move about the axis thereof so that the vanes 54 will move longitudinally toward the cam face 19 of the cam 13 (under the influence of centrifugal force., In this way, fluid entering one side of the pump will be propelled by the vanes, to the other side of the pump and the capacity of the pump may be regulated while running by moving the rack bar 83. When this is done and the cam surface is in vertical position, the pump is operating at full capacity, as is seen in Figure 2. Rack'bar 83, on

' actuation, rotates cam 13 until it is in horizontal position, or at right angles to the full capacity position. Now, the pump operates at zero capacity since one quarter of the capacity is taken in and one quarter is discharged back into the same chamber (see Figure 2). Obviously, any intermediate position of rotation causes the pump to operate at intermediate capacities between zero and full. The fluid flowing through the pump will enter either the port 23 or the port 24 and the passages 53 between the vanes to be propelled by the vanes from one side of the pump to the otheracross lands 28. Owing to the concentric curvature of the lands 28 the rotor will run closely thereto and will serve with the flns 4| and I4 and the other mechanism within the body if to separate it into a high pressure and a low pressure chamber which are not the pumping or working chambers of the pump.

The function of aperture 55 is to provide equalizing means for the pump while it is riding about the cam surface 19. As will be seen from an inspection of Figures 2 and 3, vanes 54 will slide longitudinally within radial grooves of the rotor and as a result, when vanes 54 are travelling up on the face of the cam, vanes 54 are slid into the receiving grooves and as a result, when the maximum compression is to occur, apertures 55 are within the wall of the retaining grooves and cease to function as equalizing means. However, when the vanes are at the low point of travel on cam 13, apertures 55 are exposed and serve to equalize pressure of fluid within the space deflned by the vanes. This increases the efilciency and operation of the rotor and reduces vibration thereof.

While in the foregoing there has been shown and described the preferred embodiment of this invent on it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted Having described the invention what is claimed I as new is:

1. A variable capacity vane-type pump comprising a pair of diametrically opposed ports opening thereinto, a rotor including radial slots mounted in said casing for concentric rotation about the longitudinal axis thereof, vanes movably retained in said slots, apertures in said vanes and a cam mounted in said casing to-move the vanes longitudinally of the rotor as the rotor rotates about the axis of the casing, said apertures being pressure equalizing means, said cam including a cam face disposed between the ports to engage the ends of the vanes as the rotor rotates to move the vanes into their respective slots and thereby shut the pressure equalizing means.

2. The combination of claim 1 wherein said cam includes means to vary the capacity of the pump.

3. The combination of claim 2 wherein said means is a pinion and rack operatively secured to said cam.

4. A variable capacity vane-type pump comprising a hollow circular casing having a pair of diametrically opposed ports opening thereinto, a shaft extending longitudinally in said casing, a circular block rotatably mounted on said shaft, a sleeve fitted on said block, grooves in said block and sleeve in radial alignment, vanes slidably retained in said grooves, and a cam mounted in said pump and engaging said vanes for longitudinal movement of said vanes, said shaft including grooves radially aligned with the grooves in said block and sleeve and receiving said vanes therein.

5. The combination of claim 4 wherein said vanes include apertures for equalizing pressure in the rotor.

6. The combination of claim 4 wherein said vanes include apertures for equalizing pressure in the rotor and said cam includes a cam face disposed between the ports to engage the ends of the vanes as the rotor rotates to move the vanes into their respective slots and thereby shut the pressure equalizing means.

RHEUEL H.

REFERENCES crran The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 19,783 Roberts Dec. 8, 1935 1,444,712 Smith Feb. 6, 1923 1,669,976 DeLeeuw May 15, 1928 1,743,977 Petersen Jan. 14, 1930 2,020,611 Knapp Nov. 12, 1935 2,377,886 Jastrzebski June 12, 1945 2,439,668 Mercer Apr. 13, 1948 2,466,623 Tucker et al Apr. 5, 1949 FOREIGN PATENTS Number Country Date 122,424 Switzerland Oct. 1, 1927 429,825 Germany June 8, 1928 452,829 Great Britain Aug. 31, 1938 

